21030303 has 16 divisors (see below), whose sum is σ = 33440256. Its totient is φ = 11494560.

The previous prime is 21030301. The next prime is 21030313. The reversal of 21030303 is 30303012.

It is a happy number.

It is not a de Polignac number, because 21030303 - 2¹ = 21030301 is a prime.

It is an alternating number because its digits alternate between even and odd.

21030303 is a modest number, since divided by 30303 gives 21 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21030301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21288 + ... + 22253.

It is an arithmetic number, because the mean of its divisors is an integer number (2090016).

Almost surely, 2^21030303 is an apocalyptic number.

21030303 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21030303 is a deficient number, since it is larger than the sum of its proper divisors (12409953).

21030303 is a wasteful number, since it uses less digits than its factorization.

21030303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43574.

The product of its (nonzero) digits is 54, while the sum is 12.

The square root of 21030303 is about 4585.8808314216. The cubic root of 21030303 is about 276.0250581114.

Adding to 21030303 its reverse (30303012), we get a palindrome (51333315).

The spelling of 21030303 in words is "twenty-one million, thirty thousand, three hundred three".